1. Field of the Invention
The present invention is generally related to an automated program and documentation generating system and, in particular, to a multi-stage, rule based system for managing the concurrent development of a program and documentation specifications that are then processed into program code and directly corresponding user documentation.
2. Description of the Related Art
Automatic program generation, referred to the efficient generation of application function defining sequence sets within variously as the product of program synthesizers, application generators and self generating systems, are particularly desirable as the complexity of application programs increase concurrent with an ever growing desire for different and distinct functionality at all levels of an application's operation. The ability to design, implement, maintain and document an application with broad and highly configurable functionality diminishes as the comprehensiveness of the application increases. Furthermore, training and documentation must deal with the manifold options that such applications include.
In order to alleviate the presence of unnecessary complexities and configuration options, yet avoiding the necessity of completely redesigning, implementing, maintaining and documenting dedicated application programs, a variety of program generators have been proposed. Perhaps the most common form of program generators are the form and report generator shells commonly used with or provided as part of database management systems. These systems permit reasonably complete screen and report layout definition through the identification of field locations, data types and formatting, and relations to data stored in an underlying, predefined database management system. An operative program is generated that allows user data exchange through forms and data output through reports based on a defined correspondence between form, report and database fields. The concept of a data dictionary has been introduced to, in part, support internal documentation of the relational correspondence between the defined database fields and the form and report fields. Such systems typically provide little additional support of application design, little if any support of functional logic to process data transported to or from the database, and essentially no automatic documentation of the programs generated.
In order to support a greater degree of internal functional capabilities, program synthesizers based on libraries of pre-established program parts have been proposed. A library based program synthesizer is described in U.S. Pat. No. 4,949,253. The described program generator operates from defined data to select a best match of a program part prototype from a part prototype library. Each program part prototype stored by the library is predefined and statically maintained as part of the library until selection during program generation. Upon selection, the program part prototype is processed through macro substitution to merge the interface to the part prototype with, presumably, a previously processed part prototype and, further, to unify the variable names utilized by the part prototype with those of the previously processed part prototype.
In functional terms, however, the capabilities of each part prototype is essentially fixed upon initial establishment within the part prototype library. The patent does not describe how part prototypes are selected based on function as opposed to available interface definitions. In the absence of such selectability, the functionality of the various part prototypes must be narrowly defined as against the particular function of the overall program to be generated to insure that the inherently realized logic of the program follows from the definition of the part prototype interfaces.
Another program synthesizing system is described in U.S. Pat. No. 5,315,710. This system again operates from a library termed by the patent as a program components data base. The system provides for an increased degree of freedom in interfacing program components for the automatic generation of mediating program parts that are tailored to specifically couple otherwise disparately defined program components. Thus, where two seemingly incompatible interfaces of program components must be joined, a program transformation rule base is consulted for a computative rule that can be utilized to convert the unit, base or type of data to another such representation. A data type transformation rule may be utilized to convert the data type of data from one type to another. By combination of these transformations for each of the variables through which data is passed between program components, a mediating program is assembled. The two interfaces of such a mediating program are inherently defined by the interfaces of the program components to be joined. Thus, the program components and mediating program can be assembled into a larger functional unit as part of or to complete a larger application program. However, the generated mediating program is inherently limited in its ability to alter the operational function of the program components. Consequently, the available selection of program components must be well predefined and highly consistent with the ultimately intended functionality of the application program generated.
An automatic program synthesizer system of greater functionality is described in U.S. Pat. No. 5,038,296. In this system, a system specification and set of program synthesis rules functionally define a target program through the description of operations to be performed on data represented by variables. The system specification and program synthesis rules identify these variables through functional definitions. The program synthesizer processes these definitions to resolve functionally described variables to specific variable names. Existing variables are identified by their assigned functional attributes. Where a variable has yet to have been defined for a specific set of attributes, an interpolation program is generated to define the necessary variable with the required attributes. Since the interpolation program is apparently generated by the same program generating means utilized to created the target program, the interpolation program apparently operates to combine, as necessary and appropriate, other pre-existing variables to obtain the variable value that is to be functionally stored by the newly created variable. That is, the function of the program generating means is to couple specific operations to essentially singular variables. Consequently, the functional outline of the target program provided by the system specification with functional sub-steps being defined by program synthesis rules can reasonably define a complete target program. The program synthesizer described in U.S. Pat. No. 5,038,296, however, appears to inherently require a very close concordance between the system specification and the pre-existing program synthesis rules in order to generate a target program. The disclosed system provides no identifiable method or mechanism for creating or maintaining such a concordance or insuring valid use during the operation of the program synthesizer. Furthermore, the disclosed system fails to identify any mechanism for supporting the development of the system specification and certainly fails to disclose any mechanism for generating documentation appropriate for the target program specifically produced.
In order to increase the available performance of program generators, various forms of expert systems have been incorporated. Such expert systems include finite state automata, forward and backward chaining rule based inference engines, fuzzy logic inference systems and context sensitive or guided editor systems. Although the use of such expert systems can greatly increase the apparent functionality of a program generator system, such expert systems have typically been applied in an application processing environment that, based on predefined rules, limits the perceived complexity of the operative system to the particular data input and requests made of the expert system. As such, these expert systems present an environment within which an application appears to have been constructed. Compilable or interpretable application program code is not generated. Consequently, such environments are difficult to design and maintain and make little provision for the production of documentation that is specific to a particular working application program.
Expert systems have also been utilized as components in more conventional program generators. However, in most instances, the expert systems are functionally limited to more completely or expansively enabling the selection of program part prototypes for use in the construction of the application program or inferring suitable mediation transformations necessary to interface program components. As a result, the prior art utilization of expert systems in program generator systems has not previously enabled the development of a comprehensive application program generator.